A simplified design for ultra-sensitive X-ray detectors offering more precise materials analysis has been demonstrated at the National Institute of Standards and Technology (NIST). The advance is a step toward making such devices cheaper and easier to produce. Users may eventually include the semiconductor industry, which needs better X-ray detectors to identify and distinguish between nanoscale contaminant particles on silicon wafers.
The new design, described in the Sept. 13 issue of Applied Physics Letters,* is among the latest advances in a decade of NIST research on superconducting "transition edge" sensors (TES). These cryogenic sensors absorb individual X-rays, and then measure the energy of the X-ray by measuring the resulting rise in temperature. The temperature is measured with a bilayer of normal metal and superconducting metal that changes from zero resistance (superconducting) to a slight resistance level in response to the heat from the radiation. By measuring the X-ray energy, NIST researchers can identify the X-ray "fingerprints" of particular elements.
NIST researchers have built systems offering 30 times better X-ray energy resolution than detectors now used in the semiconductor industry and are pursuing further improvements such as novel detector geometries and materials. In contrast to the usual bilayer TES design, the sensor described in the APL paper combines the normal and superconducting metals into one homogenous layer. Manganese impurities are added to a 400-nanometer-thick aluminum film to lower its superconducting transition temperature to 100 milliKelvin. Fabrication requires about half as many steps as the bilayer design. In addition, the new design exhibits less "noise" in the X-ray signals than is typical for TES sensors, as well as a low sensitivity to magnetic fields that could help in building stable instruments.
Laura Ost | EurekAlert!
Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich
Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine